Two-hand control



Dec. 5, 1939. w. c. ElcKMAN TWO-HAND CONTROL 3 Sheets-Sheet l FiledApril 2, 1937 VIH INVENTOR. VVA/ 7152 B5/(MAN ATTORNEY5 Dec. 5, 1939.

W. C. EICKMAN TWO-,HAND CONTROL Filed April 2, 1937 s sheets-sheet 2 I-l INVNTOR. WAL TEA 7. 7a/(MAN M #umg/M ATToRNEYs Dec. 5, 1939. w- QEICKMAN v l2,182,018

TWO -HAND CONTROL Filed April 2, 193'? v 3 Sheets-Sheet 3 1 INVENTOR.

WAL new 7. Ac/(MHH .QW @i M ATTORNEYS Patented Dec. 5, 1939 18ansHarris- Seybold-Potter C'ompany, Cleveland,l

Ohio, a corporation of Delaware Application April 2, 1937, Serial No.134,640

7 Claims.

'I'his invention relates to improvements in two-hand control, that is tosay a safety control requiring the use of both hands of the operator, sothat it is impossible for him to have either hand a dangerous positionduring the working stroke ofthe knife or other tool. As illustratedherein the invention is applied to a paper cut# ting machine, but itwill be apparent that in its broader aspects it is applicable to othertypes of machines in which the tool reciprocates in a vertical or someother direction.

One of the objects of the invention is the provision of a` two-handcontrol of the character stated whereinthe electrical operation of theclutch is direct and, therefore, instantaneous, as distinguished fromone in which 'the electrical control merely sets in motion mechanism forthrowing the clutch, with the action necessarily delayed on thataccount, or onein which electrical control must be operated inconjunction with a manual operation, such as throwing a lever. l

Another object rof-,the invention is the provision of means for makingpossible the jogging of the knife or other tool on the up or returnstroke as well as upon the down or work stroke, this provision beinghighly advantageous in making the necessary adjustments and settings ofthe machine preparatory to performing a given job.-

Still another object is the provision of means of a novel character forinsuringa stoppage of the tool at the end of each return stroke, so thatif theoperator inadvertently holds his hands on the controls throughoutthe-return stroke, the tool will not start on another work stroke, buton the contrary the operator must intentionally actuate the controlbuttons before a work stroke can be initiated. This is a safety'measurefor the protection of the operators helper whose duty it is to adjustthe work for the neXt cut.

Other objects and features of novelty will appear as I proceed with thedescription of that embodiment of the invention which, for the purposesof the present application, I have illustrated inthe accompanyingdrawings, in which Fig. lis a front elevational view of a fragment of apaperr cutting machine embodying the invention. f

Fig. 2 is a side view of the same, and

Fig, 3 is a wiring diagram, showing the twohand control system; which' Iemploy.

In the drawings, I0 represents the frame of a paper cutting machinehaving a Work table II, a back gauge I2, a paper clamp I3, a knife bladeI4 and a knifel bar I5. Power to operate the machine may be applied by abelt I6 running over a pulley II'I fixed on a shaft I8, which alsocarries ahy-wheel I9.

The shaft I8 extends only part-way across the .5

fmachine, where it is aligned with another vshaft 20. Shaft lcarries oneelement 2| of a friction clutch, while shaft 20 carries another element2,2 of the clutch. These two clutch elements may be,frictionally engagedby means of v'a wedge pin or finger 23 carried bya collar 24 that isslidably keyed to shaft 23 and is movable longitudinally thereupon bymeans of a yoke `25. When the wedge pin 23 is in the position shown inFig. 1 the clutch elements areengaged. 'Ihey may be disengaged bymovement of wedge pin 23 to the left in that figure.

On the opposite end of shaft20 there is secured a small gear 26fwhichmeshes with a larger gear 2l' keyed to a shaft 28. The latter shaft alsocarries a relatively small gear 29 which in turn meshes with a largegear 3B on the crank shaft 3| ofthe machine. The latter shaft carries atits endsl cranks from which the knife bar is operated through theintermediacy of the usual connecting rods. These parts are all wellknown, in the art. The speedfreducing train of gears connecting shafts20 and 3| does not appear in Fig. 1, being'located on the side of themachine- Which is cut away in that figure, but is well illustrated inFig. 2. l A

The clutch shifting yoke 25 is pinned to an operating shaft or rod 32 onwhich there is an adjustable collar 33 that forms an abutment for oneVend of a spiral spring 34, the other end of which bears against abracket 35 on the frame and through which the shaft 32 is adapted toslide. The shaft 32 also carries at one end thereof a pair of spacedcollars 35 between which is positioned the ball end of a crank 3?mounted upon a shaft 38 lwhich extends along the side ofv the machineand is suitably mounted for oscillating motion. At an intermediate pointthis shaft has keyed thereto an arm 33 in the outer end of which isoscillatably mounted a short shaft 40, through which extends a pin 4Ithat may be threaded into the shaft or otherwise fixed therein. At itslower end the pin 4! terminates in a flattened extremity 42` which isinterposed between a pair of'ang'es on the upper end of an armature 43,which isadapted to move vertically in a solenoid 44. When the solenoid44 is energized the armature 43 and the pin 4| are pulled down to thepositions shown in Fig. 1, thereby swinging arm 39 and crank 3l in theanti-clockmuch as it forms no part of the present inventionk no furtherdescription of the same will be given;

At the forward extremity of shaft 38 I'may also provide a hand lever 45for manually oscillating.

shaft 38 to set the knife bar-in motion, but it is to be understood thatthis also will not be utilized when the electrical control isfunctioning.

Twopush buttons 41 and 48 are mounted at convenient positions on themachine, )preferablyl under the forward end of table Il. These buttonsconstitute the manually operated part of the two-hand control. They mustofcourse be separated sufficiently so that both hands of the Operatorwill be required 'to'make the` control function, in all cases. Theelectrical systern'for the control of the machine includes two limitswitches which are each opened and closed once for every complete strokeof the tool. Inthe present instance these switches are illustrated at 49and 458. Their operating levers terminate in rolls l and 52 respectivelywhich run upon semicircular cams or tracks 53 and 54. When the rollers5i and 52 are raised by the cams the switches 49 andy 59 are opened,yand when they are lowered by the cams the switches are closed.

Referring now to Fig. 3, which is a diagram of the wiring system, L andL2 represent line wires.

S is a snap switch by means of which the system` may be connected withor disconnected from the line wires. A pair of conductors 55 and 56,connected withthe solenoid 44 are adapted to'be brought into circuitwith line wires L and L? by a double switch 51, which has a bias towardopen position and is arranged to be closed by the energization of anelectromagnet 58. From line Vwire L' there extends a conductor 59,`while vline wire L2 is connected with the system through two conductors68 and 6I, the electromagnet 58 being" and 55 are electrically joined bya conductorV 66 which is in communication throughv a flexible conductor61 with a conductor 68 leading to con-- ductor 59. The electromagnet 63is arranged in series with conductor 69 and a conductor 69 which extendsto one of the contacts of limit switch 49.

The two push buttons 41 and 48 are doubleacting, that is to say whenreleased by the operator push button 41 bridges two contacts `10` and1|, and push button 48 bridges two contacts 12 and 13. When they aredepressed by the operator these buttons bridge two pairs of contacts 14,15 and 16, 11. A conductor 18 connects contact with conductor 59, aconductor 419` connects contacts 1I and 12, and a conductorY 80 connectscontact 13 with one-of the contacts of limit switch 49. Contacts and 16are connected by a conductor 8|.

The switch arm 64 of relay 62, when in operative position, engages acontact 82V which'- is connected by means of a conductor 83 with contact13 of push button 48. The other contact 84 of the relay, whichcooperates with switch arm 65 is connected by means of conductor 85withv .tion as illustrated in Fig. 3, a conductor 89, limit switch 50,.and a conductor 99, the latter connectving'with'conductor 6l. Whenswitch 88 is in the dot and dashv position of Fig. 3 conductor 81v isconnected through a conductor r9| with contact 11 of push button 48.

The snap switch S and the two-way switch 88 vmay Abe mounted upon themachine in any convenient'v position, as may the relay 62 with itsswitches and the electromagnet 5 8 with its switches. i

'Operation-When the operator desires 'to use the electrical two-handcontrol,v he'v turns the snap switch S` to operative position. `Theknife isat rest at the top ofits' stroke.v In' Fig'.- 2` the crank shaftis illustrated in a position? justprior to the stopping position. Atthestop position the cam track 53has run out from underthe roller 5l,andswitch 49 is closed. vThis sets up a circuit from line -wire Lthroughswitch S, conductors 59 and'18, to contact 18 of push button 41,through-the push button land out from contact 1l through conductor 19tocontact 12 of push button 48, through that push button and out throughkcontact 1.3 to conductor 488, thence through closed switch49andconductor 69 to relay vcoil 68and out throughconductor 60 to linewire-L2. Coil63 being thus energized-,the two switches 64and`65 areclosed. This sets up a holdingxor sealing :circuit for thevrelay fromconductor 59 through conductors 68,561, 66 and switch 64 to contact 82,thence through conductors 83 and 80 to limit switch 49, andi-from thatswitch through conductor 69 to lcoil 63, and by way of .conductor 68 ytolinenwire L2.

`.'I'hisjsealing circuit. remains closed so-long as ltact 16, and by wayof conductor` 8| to contact 15 of push button'41, across to contact 14and cut through conductors 86 and l6I to electromagnet 58 and line wireL2. The energization of electromagnet 58 closes the double switch 51 andsets up a circuit from line wire L through one arm of the switch andthrough conducto-r 55 to solenoid 44 and back through conductor 56 andswitch 51 to line wire L2.

Irmrnediately after the solenoid 44 is energized the clutch fis engagedand the knife. starts to descend. f `Its descent is controlled by theoperator, who may stop it at yany point by releasing pressed 'until thecut is completed. At the' bot- 'asy tom of the stroke the. limit switch49 opens and the limit switch 50 closes. The opening of switch 49deenergizes coil 63. Hence the sealing circuit is broken both at theswitch 49 and at the Switch 64. Simultaneously the circuit through thepush buttons and electromagnet 58 is broken at the switch 65. However,the closing of limit switch 50 sets up a shunt circuit around the pushbuttons and the relay, from the line wire L through conductors 55 and 8land switch 88, and by Way of conductor 89, switch 56 and conductors 90and Si to magnet coil 58 and line Wire L2. The circuit through solenoid.44 is therefore maintained, and the knife bar ascends to complete itsstroke. When it reaches the top of its stroke the limit switch 50 againopens and the clutch is disengaged. Thelimit switch 49 then closesagain, and provided the push buttons are in their released position, sothat they bridge the contacts 70, 'H and 12, i3, the relay coil 63 isagain energized and its sealing circuit established. The machine is thenready for the neXt operation. However, should the operator keep the pushbuttons 4l and 48 depressed through the complete stroke of the knife,the machine will nevertheless stop at the end of the stroke, because acircuit cannot be set up through limit switch 49 and relay coil 63without the bridging of contacts l5, 'Il and 12, 'I3 of the pushbuttons.

In order to start the machine for a succeeding cut, it is alwaysnecessary for the operator to release the push buttons sometime afterthe cut is made, and they must remain released at the time the limitswitch 9 closes in order that no other cut may be made immediately. Theoperator therefore is required to perform a definite act before theknife may descend, and thus the operation of the knife throughinadvertence is prevented. A second descent of the knife immediatelyafter a cut was made could not harm the operator, because both of hishands would necessarily be occupied with the controls, but it might harma helper -engaged with the work of preparing the material for asucceeding cut.

The jogging of the knife bar up as well as down is useful when the knifeis being changed or when the machine is being prepared for a run ofwork. Jogging on the downward stroke is accomplished as heretoforeexplain-ed. When it is desired to jog on the upward stroke, the operatormust rst throw switch 88 to dot and dash position, which provides acircuit from line wire L' through conductors and 8l, switch 88 andconductor 9i to contact 'Fl of push button 48, and across the pushbutton to contact 'l5 and through conductor 8l to contact 'l5 of pushbutton lil, across the push button to contact 7M, and by way of contactsSES and 6l to magnet coil 58 and line wire L2. Thus the solenoid 44 maybe maintained energized momentarily with a correspondingly shortengagement of the clutch.

Variations from the described structure may be employed. Accordingly, Idesire it to be understood that the scope of the invention is to beregarded as defined exclusively by the appended claims rather than bythe foregoing description or accompanying illustration.

Having thus described my invention, I claim:

1. In a machine of the class described, a cutting tool, means forreciprocating the tool comprising a clutch, an electric shifter for saidclutch, an electric circuit controlling the shifter', a twohand controlfor said circuit, a switch in said circuit, a relay for operating saidswitch, au

electric circuit for said relay, a switch in said relay circuit, andmeans associated with the tool operating mechanism for holding said lastnamed switch closed duringthe work stroke of the tool and open duringthe returnl stroke.

2. In a machine of the class described, a cutting tool,a shaft coupledto the tool for reciprocating the latter, means for operating said shaftcomprising a clutch, an electric'shifter for throwing said clutch tooperative position, an electric circuit controlling the shifter, atwo-hand control for said circuit, said 'circuit also comprising aswitch, a relay for operating the switch, and means for energizing saidrelay during the working stroke of the tool, said means requiringinitially the release of the two-hand control.

3. In a machine of the class described, a cutting tool, a shaft coupledto the tool for reciprocating the latter, means for operating said shaftcomprising a clutch, an electric shifter for throwing said clutch tooperative position, an electric circuit controlling z the shifter, atwohand control for said circuit, said circuit also comprising a switch,a relay for operating the switch, means for actuating said relay duringthe working stroke of the tool, said means requiring initially therelease of the two-hand control, and a sealing circuit for said relay,said sealing circuit comprising a switch operated by the rotation ofsaid shaft for maintaining said sealing circuit closed during the workstroke only of the tool.

4. In a machine of the class described, a cutting tool, a shaft coupledto the tool for reciprocating the latter, means for operating said shaftcomprising a clutch, an electric shifter for throwing said clutch tooperative position, an electric circuit controlling the shifter, amanual control for said circuit, and means independent of the manualcontrol means for automatically instituting a break in the circuit atthe end of the work stroke, said means tending to automatically closesaid break at the beginning of the succeeding work stroke, the closingof' said break requiring further a positive movement of the manualcontrol at or prior to the beginning of said succeeding work stroke.

5. In a machine of the class described, a cutting tool, a shaft coupledto the tool for reciprocating the latter, means for operating said shaftcomprising a clutch, an electric shifter for throwing said clutch tooperative position, an electric circuit controlling the shifter, amanual control for said circuit, means for automatically breaking thecircuit at the end of the work stroke, said means tending toautomatically close said break at the beginning of the succeeding workstroke, the closing of said break in the circuit requiring further apositive `movement of the manual control at or prior to the beginning ofsaid succeeding work stroke, a shunt circuit around said shiftercontrolling circuit, and 'a switch therein operated by the machine tomaintain the shunt closed during the return stroke only of the tool.

6. In a machine of the class described, a vertically reciprocable tool,operating means for the tool comprising a clutch, electric means foroperating said clutch, a manual control for said electric means normallyeffective only during the ywork stroke of the tool, means fordisconnectsaid manual control at the end of the Work stroke, electric'connections independent of said manual control for maintaining theclutch in operative position on the return stroke, and a two-way switchfor disabling said electric connections and for putting said manualcontrol into operation on the return stroke, whereby the tool may bejogged on its return stroke.

. WALTER C. EICKMAN.

